The Optiflow Patency and Maturation Study

The investigation is designed as a multi-center, prospective, single-arm, clinical study of
the Optiflow performance and safety in a maximum of 180 subjects which includes one (1)
roll-in subjects per investigator (maximum of 36 roll-in subjects). Subjects will be
followed at 14 days post-procedure, 42 days post-procedure, and 90 days post-procedures.

Results will be compared to a pre-established performance goal.

Up to fifteen (15) investigational sites will participate in the investigational study.

The primary performance endpoint is the overall maturation percentage rate at 90 days.
Maturation is defined as an access site which achieves a diameter of greater or equal to 4
mm and blood flow greater or equal t0 500 mL/min as measured via duplex ultrasound.

The primary safety endpoint is a composite endpoint of serious adverse events known to be
associated with arteriovenous fistula anastomosis surgical procedures through 90 days.

Inclusion Criteria:

- Male or non-pregnant female (verified with a urine/blood pregnancy test, for women of
reproductive age).

- Life expectancy of at least one year, per the investigator's opinion.

- Diagnosed with ESRD or chronic kidney disease requiring dialysis.

- Planned upper extremity autogenous arteriovenous fistula.

- Planned anastomosis is an end of vein to side of artery configuration.

- AVF target artery and vein inner diameters are greater or equal to 3.0 mm and less
than or equal to 7.0 mm as determined by pre-operative ultrasound and confirmed
intra-operatively.

- Patient is available and willing to return for follow-up visits during the duration
of the study.

- Patient is able and willing to follow a daily aspirin and/or other
anticoagulation/antiplatelet regimen not including warfarin (see exclusion criteria).

- Patient, or their legal representative, is willing and able to provide informed
consent.

Exclusion Criteria:

- Known bleeding diathesis or coagulation disorder.

- Documented or suspected central venous stenosis.

- Uncontrolled hypotension with systolic blood pressures < 100 mg Hg at the time of
screening.

- Peripheral white blood cell count < 1.5 K/mm3 or platelet count < 75,000 cells/mm3.

- Body Mass Index (BMI) > 42.

- Transposition of the access vein is anticipated within the 90 day follow-up interval.

- Receiving anticoagulant therapy for non-cardiac indications.

- Evidence or history of an active or suspected infection within one month of
screening.

- Scheduled kidney transplant within six months of enrollment.

- History of ≥ 2 AVF and/or synthetic access graft failures.

- History of steal syndrome from a previous hemodialysis vascular access which required
intervention or abandonment.

- Current participation in another clinical trial (excluding retrospective studies or
studies not requiring a consent form).

- Anticipated surgery requiring general anesthesia during the course of follow-up.

- A history of substance abuse.

- Anticipated to be non-compliant with medical care or study requirements based on
investigator judgment.

- Need for immunosuppressive therapy at a dose greater than the equivalent of
prednisone 10 mg per day.